Various compounds have hitherto been proposed as anti-ulcer agents. Inter alia, cimetidine, which is a histamine H.sub.2 -receptor blocker, is widely used because of excellent anti-ulcer effect. However, some misgivings have been pointed out with respect to several problems encountered with cimetidine. (Refer to NIKKEI MEDICAL, 14 May, 1984, p. 26-34.)
We have made an extensive study in search of compounds which have chemical structures entirely different from those which have been proposed so far and have excellent anti-ulcer activity, and have found that 1-[4-(methylamino)-butoxy]-2-(phenylsulfonyl)benzene (Journal of Medical Chemistry, Vol. 24, No. 2, 145-148 (1981)) and related compounds have unexpected anti-ulcer activity, and upon extending our study to further encompass different compounds we attained this invention.